Finding the Fourth Proportional to 1,478.16, 2,039.96 and 815.02

Step by Step Solution

1. Step 1: Write the proportion equation
   1,478.16 : 2,039.96 = 815.02 : x
2. Step 2: Convert to fraction form
   1,478.16/2,039.96 = 815.02/x
3. Step 3: Cross multiply
   1,478.16x = 2,039.96 × 815.02
4. Step 4: Simplify right side
   1,478.16x = 1,662,599.02
5. Step 5: Solve for x
   x = 1,662,599.02/1,478.16
6. Step 6: Final answer
   x = 1,124.78